Using a repositioning splint to determine reproducibility in the color registers of a dental spectrophotometer

Objectives The purpose of this study was to assess if the use of intraoral positioning guides could increase the reproducibility of color measurements with a dental spectrophotometer. Methods Twenty‐three subjects were selected, and positioning guides for the maxillary arch of each participant were fabricated with clear 4 mm thermo‐sheets. One orifice was made in the center of the clinical crown of the upper‐right central incisor and another in the canine, with an external 6 mm diameter trephine. Color measurements were performed with a Vita EasyShade Compact IV dental spectrophotometer by the same operator in the same conditions. Forty measurements were taken per patient, 20 for each tooth, 10 with a positioning guide, and 10 without one. Before each measurement, the spectrophotometer was calibrated following the manufacturer's instructions. Results Using the Wilcoxon test to evaluate nonparametric variables, there are statistically significant differences (P